Proper use of dental floss is necessary to clean the considerable area on the interproximal surfaces of teeth which cannot be reached by the bristles of a toothbrush.
The purpose of dental floss is:                1. to dislodge and remove any decomposing food material that has accumulated at the interproximal surfaces that cannot be removed by brushing, and        2. to dislodge and remove as much as possible the growth of bacterial biofilm (plaque) upon the teeth or the superimposed calculus that has accumulated there since the previous cleaning.        
The concept of the use of dental floss for cleansing interproximal spaces appears to have been introduced by Parmly in 1819 (“Practical Guide to the Management of the Teeth”,” Collins & Croft, Philadelphia Pa.). Parmly suggested the use of waxed silk to clean teeth of persons subject to gingival inflammation. Numerous types of floss were developed and used for cleaning, until finally in 1948 Bass established the optimum characteristics of dental floss [Dental Items of Interest, 70, 921–34, (1948)].
Surprisingly, multifilament and monofilament floss marketers have ignored Bass for the past 50 plus years. Bass warned that dental floss treated with sizing, binders and/or wax produces a “cord” effect that reduces flossing efficiency dramatically. Almost all multifilament floss sold today including unwaxed floss contains binders and/or sizing substances. These “sticky” substances are used to keep the floss twists from falling off a spool during dispensing by holding the floss together.
Additionally, most multifilament floss sold at retail today is also “waxed” to assist penetration to interproximal regions. The resulting “cord” effect described by Bass often makes the floss bundle difficult to force between closely spaced teeth.
The optimum characteristics of dental floss as described by Bass in 1948 have been ignored by most interproximal device manufacturers. Specifically, Bass suggests that these waxed and sized flosses produce an undesirable “cord” effect as discussed above as distinguished from the desirable “spread effect” of unwaxed, unsized floss which flattens out and widens, with the filaments spread out. The potential for separate mechanical action of spread out filaments is nullified by this “cord” effect. Also sacrificed are the spaces between the filaments, which according to Bass are necessary to receive, hold and remove the microscopic material dislodged during flossing. Thus, the mechanical cleaning attributed to spread filaments and essentially all of the evacuation of microscopic materials from the interproximal spaces by entrapment by these spread-out filaments is impaired or sacrificed with waxed and/or sized flosses, as well as with monofilament tapes, because of this “cord” effect.
It is not surprising that shred resistance has been the basic claim of several dental tape marketers. The introduction of Gore's Glide®, with its monofilament construction, was proposed as the ultimate shred resistant floss. Historically, the typical response to shredding was to develop a “tighter” bonded and smaller diameter floss that did not spread out and did not shred. It is not difficult to see how the “ultimate cord”, i.e. monofilament tape construction, evolved from this approach. Clearly, the monofilament floss is easier to use than traditional bonded multifilament flosses, because of this no-shredding feature. However, shred resistance is achieved with a sacrifice in entrapment and removal of material dislodged during flossing.
It is generally accepted that floss is not a “user-friendly” product, i.e. it is difficult to do. It causes pain and bleeding and it results in a bad taste in the mouth. Most market researchers agree that anything that can be done to make flossing more positive should be implemented to encourage more frequent flossing and more wide spread floss use. The addition to floss of various coatings including those: saliva-soluble, crystal-free coatings of the present invention which contain chemotherapeutic ingredients, mouth conditioning substances such as silicones, cleaners and Soft Abrasives™ that leave a “clean, just brushed feeling” as taught by the present invention are all sources of positive feed back to the flosser that would be considered encouraging and supportive. To achieve these advances requires basic changes in floss construction and in physical chemistry of floss additives as well as coating technology that avoids the “cord” effect characteristic of waxed floss and monofilament tape and is particularly responsive to the need for entrapment and removal of material dislodged during flossing.
Shred-resistant monofilament interproximal devices are described and claimed in U.S. Pat. No. Re 35,439; 3,800,812; 4,974,615; 5,760,117; 5,433,226; 5,479,952; 5,503,842; 5,755,243; 5,845,652; 5,884,639; 5,918,609; 5,962,572; 5,998,431; 6,003,525; 6,083,208; 6,148,830; 6,161,555 and 6,027,592. These monofilament dental tapes generally have serious shortcomings in: gentleness, delivering coatings during flossing, being handled easily and conveniently during flossing and entrapping and removing material dislodged during flossing.
Shred-resistant, polytetrafluoroethylene (PTFE) based monofilament interproximal devices are described in: U.S. Pat. Nos. 5,209,251; 5,033,488; 5,518,012; 5,911,228; 5,220,932; 4,776,358; 5,718,251; 5,848,600; 5,787,758 and 5,765,576. To date, no commercial versions of these monofilament tapes have been coated effectively, nor can they be used to deliver active ingredients, interproximally and subgingivally during flossing, nor can monofilament tapes entrap and remove materials from interproximal spaces. Handling during flossing is difficult. Most have to be folded to provide a consumer acceptable edge. Many are plagued with serious dimensional inconsistency problems, as well.
Multifilament, interproximal devices are described and claimed in U.S. Pat. Nos. 5,033,365; 3,943,949; 6,080,481; 5,830,495; 2,667,443; 4,638,823; 4,029,113; 2,772,205; 4,627,975; 4,414,990; 3,699,979; 3,897,795; 3,838,702; 4,776,358; 5,718,251; 5,603,921; 5,558,901; 5,423,337; 5,357,990; 4,986,288; 3,897,795; 3,928,618; 5,433,226 and 4,033,365. Most of these flosses would not be classified as shred resistant.
The Hill, et al., patents, namely U.S. Pat. Nos. 4,911,927; 5,098,711; 5,165,913 and 5,711,935, describe compression loaded multifilament flosses. All multifilament interproximal devices pose major consumer problems in the areas of shredding, breaking, etc., with the texturized multifilament dental flosses exhibiting even greater shredding and breaking shortcomings. It is these shortcomings of the multifilament flosses in general that were instrumental in the commercial success of shred-resistant PTFE and other monofilament devices.
The production of ultra-high molecular weight, stretched polyethylene film that has been slit into various tapes of varying width and thickness, which is then fibrillated, i.e. penetrated with various cutting means, to produce these micromesh tapes suitable for compression loading to produce interproximal devices of the present invention is described and claimed in U.S. Pat. Nos. 4,879,076; 4,998,011; 5,002,714; 5,091,133; 5,106,555; 5,106,558; 5,200,129; 5,598,373; 5,693,708 and 5,723,388. Specific methods of fibrillating films are described in U.S. Pat. Nos. 2,185,789; 3,214,899; 2,954,587; 3,662,930 and 3,693,851 and Japanese Patent Publication Nos. 13116/1961 and 16909/1968. Suitable fibrillating tools include fibrillating rollers, various needle bars, separating cones, needle rings and ceramic blades and are available from Burckhardt AG, Basel, Switzerland. Particularly preferred fibrillating tools for producing the micromesh interproximal tapes suitable for coating according to the present invention include: needle bars, tapping screw-like fibrillators or file-like fibrillators. The latter two are illustrated in FIGS. 3 and 4 of the drawings. The fibrillator illustrated in FIG. 4, described as a file-like fibrillator, is the subject of Japanese Utility Model No. 38980/1976.
All of the foregoing references are hereby incorporated by reference.
Effective oral hygiene requires that three control elements be maintained by the individual:
Physical removal of stains, plaque (biofilm) and tartar. This is accomplished in the strongest sense by scraping and abrasion in the dentist's office. Self administered procedures are required frequently between visits and range from tooth brushing with an appropriate abrasive toothpaste, through flossing and water jet action, down to certain abrasive foods and even the action of the tongue against the tooth surface.
Surfactant Cleansing, where the source of the surfactant is generally: toothpaste, mouth rinse and/or dental floss. This is required to remove: food debris and staining substances before they adhere to the tooth surfaces; normal dead cellular (epithelial) material which is continually sloughed off from the surfaces of the oral cavity and microbial degradation products derived from all of the above. Besides the obvious hygienic and health benefits related to simple cleanliness provided by surfactants, there is an important cosmetic and sense-of-well-being benefit provided by surfactant cleansing. Research has shown that the primary source of bad breath is the retention and subsequent degradation of dead cellular material sloughed off continuously by the normal, healthy mouth or dislodged from interproximal surfaces by flossing and not subsequently entrapped and removed by the interproximal device.
Frequency of Cleansing. This is perhaps the most difficult to provide in today's fast-paced work and social environment. Most people recognize that their teeth should be brushed at least 3 times a day and flossed at least once a day. The simple fact is that most of the population brush once a day, some brush morning and evening, but precious few carry toothbrush and dentifrice to use the other three or four times a day for optimal oral hygiene. Consumer research suggests that the population brushes an average of 1.3 times a day. Most surprising, less than 10% of adults floss regularly. Reasons offered for not flossing: difficult to do, painful, does not appear to be working, inconvenient and leaves a bad taste. Overall, floss is not perceived as a “consumer friendly” product.